517 Track-Type Skidder Power Shift Transmission Caterpillar

Systems Operation

Note: Refer to Systems Operation, RENR2025 for a description of the systems operation for the 517 Track-Type Skidder power train.

Specifications

Note: Refer to Specifications, RENR2024 for the specifications with illustrations. If the specifications in Specifications, RENR2024 and Systems Operation, RENR2025 are different, look at the printing date on the cover of each book. Use the specifications in the book with the latest date.

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Personal injury or death can result from machine movement. When tests and adjustments are made to the transmission or the torque converter, the parking brake must be disengaged. To prevent movement of the machine and personal injury perform the procedure that follows.

1. Lower all attachments to the ground.

2. Put blocks in front of the tracks and behind the tracks.

3. Allow only approved personnel on the machine. Keep all other personnel off the machine and in clear view of the operator.

4. When testing must be done in a closed area, activate the service brakes when the parking brake cannot be used. When possible, activate the service brakes while performing tests.

Note: All tests and adjustments must be made with the power train system oil at normal operating temperature. Be sure that the linkage adjustments are correct before tests are performed.

Power Train Hydraulic System

Illustration 1	g00477557
Transmission hydraulic controls (1) Priority valve (part of the oil filter) (2) Power train oil pump (3) Oil sump in the case of the case and frame (4) Torque converter outlet relief valve (5) Oil cooler (6) Torque converter (7) Load piston (8) Pressure differential valve (9) No. 1 clutch (10) No. 2 clutch (11) No. 3 clutch (12) Transmission lubrication (13) Direction selection spool (14) Ratio valve for the torque converter (15) Modulation relief valve (16) Steering clutch and brake lubrication (17) Speed selection spool (18) Body of the pressure and selector control valve (19) No. 5 clutch (20) No. 4 clutch (21) Steering and brake control valve (22) Oil filter (A) Pressure tap for the transmission oil pump (B) Pressure tap for the converter outlet (C) Pressure tap for direction clutch (P2) ( D) Pressure tap for speed clutch (P1) ( E) Pressure tap for converter inlet (P3)

Location of The Pressure Taps

Illustration 2	g00477549
Right side of the steering clutch and brake control valve (21) Steering clutch and brake control valve (A) Pump (priority valve)

Note: A port on the left side of the valve at the same location may also be used to check the pump and priority valve pressure.

Illustration 3	g00477550
(4) Torque converter outlet relief valve (B) Torque converter outlet pressure tap

Illustration 4	g00477552
(C) Direction clutch (P2) ( D) Speed clutch (P1) ( E) Converter inlet (P3) ( F) Transmission lube

Illustration 5	g00477553
(C) Direction clutch (P2) ( D) Speed clutch (P1) ( E) Converter inlet (P3) ( F) Transmission lube for machines that are equipped with a swing boom

Illustration 6	g00477551
(G) Left steering clutch (H) Left brake (J) Right brake (K) Right steering clutch

Illustration 7	g00477555
(L) Steering clutch and brake lubrication pressure taps

The front pressure tap is for the right side of the machine. The rear pressure tap is for the left side of the machine.

Illustration 8	g00477690
(LP) Load piston plug

Transmission Pressure Chart

Table 1

Transmission Pressure Chart
Pressure	Pressure Tap	Low Idle	High Idle	Adjustment
Priority Valve	(A)	2900 ± 140 kPa (420 ± 20 psi)	Add or remove valve adjustment shims 25 to priority valve (1). See Table 2.
Converter Outlet Pressure	(B)		400 kPa (58 psi) minimum The service brakes are activated and the transmission selector lever is in THIRD SPEED FORWARD. The torque converter is in a stall condition.	Add or remove valve adjustment shims (24) to converter outlet relief valve (4). See Table 2.
Direction Clutch (P2)	(C)	380 ± 55 kPa (55 ± 8 psi) lower than the pressure of speed clutch pressure tap (D) Transmission selector lever in any FORWARD or REVERSE speed Load piston plug (LP) is installed.	380 ± 55 kPa (55 ± 8 psi) lower than the pressure of speed clutch pressure tap (D) Transmission selector lever in any FORWARD or REVERSE speed Load piston plug (LP) is installed.	No adjustment Direction clutch pressure is controlled by the spring rate for the pressure differential valve.
Speed Clutch (P1) Initial Pressure	(D)	530 ± 35 kPa (77 ± 5 psi) with the transmission selector lever in the NEUTRAL position Load piston plug (LP) is removed.		Add or remove valve adjustment shims (23) to selector and pressure control valve (18). See Table 2.
Speed Clutch (P1)	(D)	345 kPa (50 psi) (maximum) less than the pressure with the engine speed at maximum RPM. Transmission selector lever in any FORWARD speed or REVERSE speed Load piston plug (LP) is installed.	2550 ± 105 kPa (370 ± 15 psi) with the transmission selector lever in any FORWARD or REVERSE speed. Load piston plug (LP) is installed.	No adjustment Final pressure is controlled by the initial pressure setting.
Converter Inlet Pressure (P3)	(E)		1000 kPa (145 psi) maximum with cold oil	No adjustment
Transmission Lubrication Oil	(F)	12 kPa (1.5 psi) Minimum	130 ± 30 kPa (19 ± 4.5 psi)	No adjustment
Steering Clutch and Brake lubrication	(L)		115 kPa (17 psi) minimum	No Adjustment

Pressure Differential Valve Test

Pressure Differential Valve Operation

1. With a stopped engine, move the transmission selector lever to any position except NEUTRAL.

2. Start the engine and run the engine at high idle.

   1. Direction clutch pressure (P2) must be 0 kPa (0 psi).

   2. Speed clutch pressure (P1) must be 2550 ± 105 kPa (370 ± 15 psi).

3. Move the transmission selector lever to NEUTRAL. Then move the lever to THIRD SPEED FORWARD, or to REVERSE.

   1. Direction clutch pressure (P2) must be 380 ± 55 kPa (55 ± 8 psi) lower than the speed clutch pressure.

      Note: If the machine is equipped with a neutral start switch, the transmission selector lever must be in NEUTRAL in order to activate the starter.

Transmission Oil Pump (Bench Test Specifications)

Type ... Gear

Number of sections ... Two

Rotation at the pump drive end ... Counterclockwise

Output of the transmission clutch control section of the pump

Use SAE 10W oil at 49°C (120°F). Check the output at the following pump speed and pressure:

Minimum output ... 57 L/min (15 US gpm)

Pump speed ... 1800 RPM

Pressure ... 1725 kPa (250 psi)

Output of the steering clutch and brake lubrication section of the pump

Use SAE 10W oil at 49°C (120°F). Check the output at the following pump speed and pressure:

Minimum output ... 152 L/min (40 US gpm)

Pump speed ... 1800 RPM

Pressure ... 345 kPa (50 psi)

Table 2

Valve Adjustment Shims Pressure Change To The Valve By Removal Or Addition Of One Shim
Part Numbers For Shims	Thickness	Change in Pressure	Location
(23)
5M-9622	1.60 mm (.063 inch)	98 kPa (14.20 psi)	Load Piston (7)
5M-9623	0.90 mm (.035 inch)	57 kPa (8.3 psi)
5M-9624	0.25 mm (.010 inch)	16 kPa (2.3 psi)
(24)
4M-1751	0.40 mm (.016 inch)	19 kPa (2.7 psi)	Converter Outlet Relief Valve (4)
5S-7001	0.90 mm (.035 inch)	40 kPa (6.0 psi)
(25)
4M-1751	0.40 mm (.016 inch)	140 kPa (20.4 psi)	Priority Valve (1)
5J-2722	1.20 mm (.048 inch)	420 kPa (61.3 psi)

Table 3

Position of The Transmission Selector Lever	Clutch Engagement In The Transmission
Neutral	3
First Speed Forward	2 and 5
Second Speed Forward	2 and 4
Third Speed Forward	2 and 3
First Speed Reverse	1 and 5
Second Speed Reverse	1 and 4
Third Speed Reverse	1 and 3

Illustration 9	g00479049
Transmission selector and pressure control valve (18) Body of the transmission selector and pressure control valve (7) Load piston (23) Shims

Illustration 10	g00479050
Outlet relief valve for the torque converter (4) Relief valve for converter outlet (24) Shims

Illustration 11	g00479622
Location of the priority valve (1) The priority valve is located in the oil filter housing. (22) Oil Filter

Illustration 12	g00479623
The priority valve is located in the oil filter housing. (1) Priority valve (25) Shims

Steering And Brakes

Steering And Brake Pressure Chart

Table 4

Steering And Brake Pressure Chart(1)
Steering Lever or Brake Pedal Position	Left Clutch (G)	Right Clutch (K)	Left Brake (H)	Right Brake (J)	Adjustment
No lever or pedal movement	2750 ± 150 kPa (400 ± 22 psi)	2750 ± 150 kPa (400 ± 22 psi)	2750 ± 150 kPa (400 ± 22 psi)	2750 ± 150 kPa (400 ± 22 psi)	Footnote (2) Footnote (3)
The left lever is pulled back completely and there is no movement of the right lever or the brake pedal.	Less than 70 kPa (10 psi)	2750 ± 150 kPa (400 ± 22 psi)	225 ± 40 kPa (33 ± 6 psi)	2750 ± 150 kPa (400 ± 22 psi)	Footnote (2) Footnote (3)
The right lever is pulled back completely and there is no movement of the right lever or the brake pedal.	2750 ± 150 kPa (400 ± 22 psi)	Less than 70 kPa (10 psi)	2750 ± 150 kPa (400 ± 22 psi)	225 ± 40 kPa (33 ± 6 psi)	Footnote (2) Footnote (3)
The brake pedal is pushed down completely and there is no movement of the lever.	2750 ± 150 kPa (400 ± 22 psi)	2750 ± 150 kPa (400 ± 22 psi)	Less than 70 kPa (10 psi)	Less than 70 kPa (10 psi)	Footnote (2) Footnote (3)
The parking brake is on and there is no movement of the lever or the brake pedal.	2750 ± 150 kPa (400 ± 22 psi)	2750 ± 150 kPa (400 ± 22 psi)	300 kPa (44 psi) Maximum	300 kPa (44 psi) Maximum	Adjust the linkage for the parking brake.

(1)	The pressure values that are shown in the table are with the engine speed at the maximum and the transmission in NEUTRAL.
(2)	Make sure that the following adjustments are correct before you adjust any system pressures: steering and brake control linkage, parking brake linkage, clutch lever and spring assemblies.
(3)	Use shims (26) for the steering clutches and shims (27) for the brakes in order to adjust the 2750 ± 150 kPa (400 ± 22) pressure. Use shims (28) in order to adjust the 225 ± 40 kPa (33 ± 6 psi) residual pressure for the brake. The “Less than 70 kPa (10 psi)” pressure is not adjustable.

Illustration 13	g00477551
(G) Left steering clutch (H) Left brake (J) Right brake (K) Right steering clutch

Illustration 14	g00483014
Steering and brake control valve (26) Shims for adjusting clutch pressures (27) Shims for adjusting brake pressures (28) Shims for adjusting residual pressure for the brakes

Table 5

Valve Adjustment Shims Pressure Change To The Valves By The Removal Or Addition Of One Shim
Part Number For Shim	Thickness	Change In Pressure	Location
(26) (27)
5M-9622	1.60 mm (.063 inch)	122 kPa (17.7 psi)	Steering Clutch and Brake Spools
5M-9623	0.90 mm (.035 inch)	71 kPa (10.3 psi)
5M-9624	0.25 mm (.010 inch)	19 kPa (2.8 psi)
(28)
7G-3046	0.25 mm (.010 inch)	38 kPa (5.5 psi)	Brake Spools
7G-3177	1.80 mm (.031 inch)	118 kPa (17.1 psi)
3T-6822	1.78 mm (.070 inch)	267 kPa (38.7 psi)

Note: Before a pressure adjustment is made, make sure that the valve spring is not weak or broken.

Linkage Adjustments

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Steering clutch and brake control linkage adjustments should be made only with the engine OFF. Accidental disengagement of the parking brake while the engine is running could cause sudden machine movement and personal injury.

Linkage For The Transmission Controls And The Parking Brake

Illustration 15	g00480978
Transmission control linkage (1) Rod (2) Parking brake lever (3) Rod assembly (4) Rod end (5) Rod assembly (6) Lever (7) Rod assembly (8) Rod assembly (9) Lever (10) Lever (11) Rod assembly (12) Rod assembly (13) Rod assembly (A) Run position

Torque for all 3/8 inch locknuts (jam nuts) that hold the rod ends in place on the rods ... 14 ± 4 N·m (124 ± 35 lb in)

Torque for all 3/8 inch locknuts (jam nuts) on the rod end ballstuds ... 25 ± 7 N·m (221 ± 62 lb in)

Note: All rod assembly measurements must be made in a straight line between the centerlines of the rod end mounting holes.

(3) Assembled length of rod assembly ... 240 ± 1 mm (9.45 ± .04)

(7) Assembled length of rod assembly ... 554 ± 1 mm (21.81 ± .04)

(8) Assembled length of rod assembly ... 435 ± 1 mm (17.13 ± .04)

(11) Assembled length of rod assembly ... 471 ± 1 mm (18.54 ± .04)

(12) Assembled length of rod assembly ... 367 ± 1 mm (14.45 ± .04)

(13) Assembled length of rod assembly ... 113 ± 1 mm (4.45 ± .04)

Procedure to Adjust the Transmission Control Linkage

Illustration 16	g00481232
Transmission control linkage (9) Direction control lever (10) Speed control lever (14) Shift lever

Illustration 17	g00481236
Transmission control linkage (15) Rod assembly (16) Rod assembly (17) Lever (18) Lever

1. Position shift lever (14), as shown. See Illustration 16.

2. At the transmission valve for speed control, position lever (10) in NEUTRAL, as shown. See Illustration 16. Adjust rod (16) for a free fit of the bolt in lever (18).

3. At the transmission valve for direction control, position lever (10) in FORWARD, as shown. See Illustration 16. Adjust rod (15) in order to obtain a free fit of the bolt in lever (18). See Illustration 17.

Parking Brake Adjustment Procedure

1. Move parking brake lever (2) downward to the BRAKE ON position. Adjust rod (1) until the end of the rod fits freely in parking brake lever (2).

2. Tighten the locknut on rod (1) to a torque of 5 ± .5 N·m (44 ± 4 lb in).

3. Adjust rod assembly (3) to the specified length. Install the adjusted rod assembly.

   Note: Do not change the length of rod assembly (3) in further adjustments.

4. Disconnect the upper end of rod assembly (5).

5. Pull up on lever (6) until the detents are fully depressed. Adjust the length of rod assembly (5) until the pin fits freely through upper rod end (4). Then, turn upper rod end (4) clockwise by two full turns in order to shorten the rod. Install rod assembly (5).

6. Inorder to check the parking brake adjustment, install a 0 to 4000 kPa (0 to 600 psi) pressure gauge on either the left or the right pressure tap for the brakes.

7. Start the engine and run the engine at low idle.

8. With the parking brake lever in the BRAKE ON position, the gauge must read less than 300 kPa (44 psi). If the pressure is not less than 300 kPa (44 psi), shorten rod assembly (5) and check the pressure again.

9. Move the parking brake lever to the BRAKE OFF position. The pressure gauge must read 2750 ± 150 kPa (400 ± 22 psi). If the pressure reading is low, make rod assembly (5) longer. Check the pressure reading again.

10. Check the pressure at pressure tap (P1) after the linkage adjustments in Step 8 and 9 are completed. Install a 0 to 4000 kPa (0 to 600 psi) pressure gauge at pressure tap (P1) on the transmission. While the engine is running at low idle, move the parking brake lever from BRAKE ON to BRAKE OFF. Move the lever for the full travel distance in both directions. The gauge should show the same pressure with the parking brake in the ON position or the OFFposition.

11. If the pressure gauge at tap (P1) does not show the same pressure in both positions, the parking brake valve is leaking oil. You must make further adjustments to the linkage. Use the following instruction to make those adjustments to the linkage.

    1. If (P1) pressure is less with the parking brake lever in the OFF position, lengthen rod (5).

    2. If (P1) pressure is less with the parking brake lever in the ON position, shorten rod (5).

12. If linkage adjustments are made in Step 11, repeat the pressure checks in Steps 8, 9, and 10.

Steering Clutch and Brake Control Linkage Adjustment

Illustration 18	g00481925
Linkage for steering clutch and brake and service brake (1) Steering clutch control lever (2) Steering clutch control lever (3) Brake pedal (4) Stop bolt (5) Locknut (6) Rod assembly (7) Rod assembly (8) Bolt (9) Lever (10) Rod assembly (11) Rod assembly (12) Rod assembly (13) Bumpers (A) Dimension 1.0 + 1.0 − 0.5 mm (.04 + .04 − .02 inch) (B) Dimension 7.0 ± 1.0 mm (2.75 ± .04 inch) (C) Dimension 146 mm (5.75 inch)

Torque for all 3/8 inch locknuts (jam nuts) that hold the rod ends in place on the rods ... 14 ± 4 N·m (124 ± 35 lb in)

Note: All rod assembly measurements must be made in a straight line between the centerlines of the rod end mounting holes.

(8) Torque for four bolts ... 47 ± 4 N·m (35 ± 3 lb ft)

(10) Assembled length of rod assembly ... 367 ± 3 mm (14.45 ± .12 inch)

(12) Assembled length of rod assembly ... 266 ± 1.5 mm (10.47 ± .06 inch)

1. Adjust rod assembly (12) to the correct length. Install the rod assembly.

2. Adjust rod assemblies (10) and (11) in order to provide a clearance between clutch levers (1) and (2) and the opening in the platform of 7.0 ± 1.0 mm (.28 ± .04 inch), as shown. See view (A-A) in Illustration 18.

3. Adjust bumpers (13) to dimension (A) of 1.0 + 1.0 − 0.5 mm (.04 + .04 − .02 inch).

Service Brake Pedal Linkage Adjustment

1. Assemble brake pedal (3) on the shaft so that the front edge of the pedal is dimension (C) of 146 mm (5.75 inch) from the floorplate. Align the timing mark on the shaft with the centerline of slot in the pedal. Move down one splined tooth from this position in order to obtain dimension (C).

2. Adjust rod assembly (6) to the correct length and install the rod assembly.

3. Disconnect rod assembly (7) from lever (9).

4. Rotate lever (9) counterclockwise until resistance is felt.

5. Adjust the length of rod assembly (7) in order to obtain a free fit in lever (9).

6. Push down on the service brake pedal until lever (9) stops.

7. While the brake pedal is pushed down fully, adjust bolt (4) until the head of the bolt contacts the brake pedal.

8. Release the brake pedal. Turn bolt (4) outward by an additional 1/2 turn. Tighten locknut (5).

   Note: Inorder to bring the service brake pedal closer to the operator, align the timing mark on the shaft with the centerline of the slot in the pedal. This will give a dimension (B) of 176 mm (6.9 inch).

Adjustment Procedure for Clutch Levers and Spring Assemblies

Illustration 19	g00482155
Clutch lever and spring assembly (1) Roller (2) Cover (3) Bolt (4) Spring assembly (5) Clutch lever (6) Plunger

Note: This adjustment should be made before any system pressures are adjusted.

1. Remove cover (2) and loosen bolt (3).

2. Move clutch lever (5) until roller (1) comes in contact with plunger (6). The roller must not depress the plunger. Only make contact.

3. Move spring assembly (4) until the pin of the spring assembly is in the front detent of the clutch lever, as shown. See Illustration 19.

4. Tighten bolt (3).

5. Install cover (2).

6. Repeat this procedure for the other clutch lever.

Testing and Adjusting

Power Train Hydraulic System

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Personal injury or death can result from sudden machine movement. Sudden movement of the machine or release of oil under pressure can cause injury to persons on or near the machine. To help prevent possible injury, perform the procedure that follows before testing and adjusting the hydraulic and steering system:

1. Move the machine to a smooth, horizontal location. Move away from working machines and personnel. Lower the implements to the ground.

2. Permit only one operator on the machine. Keep all other personnel away from the machine or in clear view of the operator.

3. Engage the parking brake.

4. Stop the engine.

5. Put blocks in front of the tracks and behind the tracks.

6. Make sure that all hydraulic pressure is released before any of the fittings, hoses, or components are loosened, tightened, removed, or adjusted.

Procedure

When you are defining a problem in the power train hydraulic system, the following procedure should be followed. First, do visual checks. If the visual checks are completed and the problem has not been identified, do operation checks. If you have not completely identified the problem, do the instrument tests. This procedure will help identify problems in the power train hydraulic system. When the problem is defined, go to the troubleshooting section of this manual. There may be more than one cause for a problem. The troubleshooting section will list the probable causes of a known problem. The troubleshooting section may suggest specific inspections or instrument tests be done. These inspections and tests will help identify the most probable causes of the problem.

Use this section as a reference in order to locate problems and correct problems in the power train hydraulic system. If additional checks need to be made, use the 6V-4160 Test Group for transmission hydraulics. Locations of the pressure taps and procedures for testing and adjusting are contained in this manual.

Visual Checks

1. Check the power train oil level.

2. Check the oil level in the final drives.

3. Check all of the oil lines, hoses, and connections for leaks and damage. Look for oil on the ground under the machine.

4. Check the control linkages for the transmission and the steering clutches and brakes for damage and/or adjustment.

5. Check the adjustment of the track.

6. Check the screens and filters for foreign material.

   1. Bronze colored particles are an indication of failure of the clutch.

   2. Shiny steel particles are an indication of a pump failure.

   3. Rubber particles are an indication of a seal failure or a hose failure.

   4. Aluminum particles are an indication of a torque converter failure.

If you find metal or rubber particles, all components of the power train oil system must be cleaned out. Always replace damaged parts with new parts.

Problem Checklist

Transmission Problem List

1. The transmission does not operate in any speed. The transmission does not engage in all speeds or there is clutch slippage in all speeds.

2. The transmission does not shift.

3. Slow shifts.

4. The transmission engages very suddenly. This sudden engagement causes rough shifting.

5. The transmission operates in FORWARD speeds only.

6. The transmission operates in REVERSE speeds only.

7. The transmission will not operate in FIRST speed FORWARD or in REVERSE.

8. The transmission does not operate in SECOND speed FORWARD or in REVERSE.

9. The transmission does not operate in THIRD speed FORWARD or in REVERSE.

10. The transmission does not disengage when the direction selector lever is in NEUTRAL.

11. The transmission engages but the machine will not move.

12. The transmission gets hot.

13. There is abnormal noise in the transmission oil pump.

Torque Converter Problem List

1. The torque converter gets hot.

2. High torque converter inlet pressure.

3. Low torque converter inlet pressure.

4. There are noises in the torque converter that have the sound of metal to metal contact.

5. Too much oil is in the torque converter housing.

6. There is noise in the planetary gears or in the torque converter.

Braking Problem List

1. The brakes will not engage.

2. Both brakes will not release.

Transmission

No. 1. Problem

The transmission does not operate in any speed. The transmission does not engage in all speeds or there is clutch slippage.

Probable Cause

1. Low oil pressure in the system. Low oil pressure can be caused by one of the following problems.

   1. Low oil level

   2. The control linkage is loose or the adjustment is not correct.

   3. Failure of the transmission oil pump or the pump drive

   4. Air leakage on the inlet side of the transmission oil pump

   5. Incorrect priority valve adjustment

   6. Oil leakage inside the transmission

   7. Incorrect adjustment of the modulation relief valve or the valve does not close.

   8. The load piston or the differential valve operation is incorrect.

2. Mechanical failure in the transmission

3. Failure of the torque converter

4. Failure of the transfer and bevel gears

5. Incorrect steering clutch operation

6. Failure in the final drives

No. 2. Problem

The transmission does not shift.

Probable Cause

1. The control linkage is loose or the adjustment is not correct.

2. Low oil level

3. Low clutch pressures

No. 3. Problem

Slow shifts.

Probable Cause

1. Low oil pressure

2. The adjustment of the control linkage is not correct.

3. Air leakage on the inlet side of the transmission oil pump.

4. The load piston or the differential valve does not move.

No. 4. Problem

The transmission engages very suddenly. This sudden engagement causes rough shifting.

Probable Cause

1. The initial setting of the modulation relief valve is not correct.

2. The load piston or the differential valve does not move.

3. Valve springs that are weak or damaged

No. 5. Problem

The transmission operates in FORWARD speeds only.

Probable Cause

1. The control linkage is loose or the adjustment is not correct.

2. No. 1 clutch is not engaged or the clutch slips. This can be caused by one of the following problems.

   1. Low oil pressure

   2. Oil leakage

   3. Excessive wear on the discs and plates

   4. Broken parts in the clutch

No. 6. Problem

The transmission operates in REVERSE speeds only.

Probable Cause

1. The control linkage is loose or the adjustment is not correct.

2. No. 2 clutch is not engaged or the clutch slips. This can be caused by one of the following problems.

   1. Low oil pressure

   2. Oil leakage

   3. Excessive wear on the discs and plates

   4. Broken parts in the clutch

No. 7. Problem

The transmission does not operate in FIRST speed FORWARD or in REVERSE.

Probable Cause

1. No. 5 clutch is not engaged or the clutch slips. This can be caused by one of the following problems.

   1. Low oil pressure

   2. Oil leakage

   3. Excessive wear on the discs and plates

   4. Broken parts in the clutch

No. 8. Problem

The transmission does not operate in SECOND speed FORWARD or in REVERSE.

Probable Cause

1. No. 4 clutch is not engaged or the clutch slips. This can be caused by one of the following problems.

   1. Low oil pressure

   2. Oil leakage

   3. Excessive wear on the discs and plates

   4. Broken parts in the clutch

No. 9. Problem

The transmission does not operate in THIRD speed FORWARD or in REVERSE.

Probable Cause

1. No. 3 clutch is not engaged or the clutch slips. This can be caused by one of the following problems.

   1. Low oil pressure

   2. Oil leakage

   3. Excessive wear on the discs and plates

   4. Broken parts in the clutch

No. 10. Problem

The transmission does not disengage when the direction selector lever is in NEUTRAL.

Probable Cause

1. The control linkage is loose or the adjustment is not correct.

2. The direction clutch is engaged and the clutch does not release.

No. 11. Problem

The transmission engages but the machine will not move.

Probable Cause

1. Failure of the final drives

2. Failure of the steering clutches

3. Failure of the transfer and bevel gears

4. The gears in the transmission will not move. This may be caused by one of the following problems.

   1. Too many clutches that are engaged

   2. Mechanical failure in the transmission

5. Mechanical failure in the torque converter

No. 12. Problem

The transmission gets hot.

Probable Cause

1. Low oil level

2. High oil level

3. Cores of the oil cooler are not completely open.

4. Low oil flow because of wear in the transmission oil pump

5. Long periods of operation with the torque converter at stall speed or near stall speed

6. Too much resistance between the clutch plates and the discs

   Note: This resistance exists despite the disengagement of the clutches.

No. 13. Problem

There is abnormal noise in the transmission oil pump.

Probable Cause

1. Loud sounds at short intervals that indicate particles are going through the pump. These noises can be caused by pump cavitation.

2. Constant loud noises can indicate pump failure.

3. Air leakage at the inlet side of the pump can cause abnormal noises.

Torque Converter

The information that follows can be used to diagnose problems in the torque converter. This information does not list every possible problem. The problem could be in the engine or the transmission.

No. 1. Problem

The torque converter gets hot.

Probable Cause

1. Defective temperature gauge or sending unit

2. Long periods of operation with the torque converter at stall speed or near stall speed

3. Cooling system operation is not correct.

   1. Cores in the oil cooler are not completely open.

   2. Restriction in the oil cooler lines

4. Low oil pressure

   1. Low oil level

   2. The ratio valve in the torque converter is not operating correctly.

   3. Torque converter outlet relief valve that is not closing

   4. Leakage around seals in the torque converter

5. Air in the oil system

6. Torque converter scavenge line that is restricted or plugged

7. Mechanical failure in the torque converter

No. 2. Problem

High torque converter inlet pressure.

Probable Cause

1. Ratio valve in the torque converter that is not operating correctly

2. Restrictions in the torque converter outlet relief valve

3. Restrictions in the outlet line to the oil cooler

No. 3. Problem

Low torque converter inlet pressure.

Probable Cause

1. Defective torque converter charging pump

2. Ratio valve in the torque converter

   1. Dirt or foreign material will not allow the valve to close.

3. Torque converter outlet relief valve

   1. Weak spring

   2. Dirt or foreign material will not allow the valve to close.

4. Leakage around seals in the torque converter

No. 4. Problem

There are noises in the torque converter that have the sound of metal to metal contact.

Probable Cause

1. Bearings with excessive wear or damage

2. Loose turbine, impeller, or stator blades

3. Too much side load on the output shaft

Brakes

No. 1. Problem

The brakes will not engage.

Probable Cause

1. The operation of the brake pedal linkage or the adjustment of the linkage is not correct.

2. The valve spool in the brake control valve does not move freely.

3. The brake plates or the discs have excessive wear or damage.

No. 2. Problem

Both brakes will not release.

Probable Cause

1. The operation of the brake pedal linkage or the adjustment of the linkage is not correct.

2. The valve spool in the brake control valve does not move freely.

3. Low oil pressure

4. The parking brake valve and the linkage does not work correctly.

Checks During Operation

Operate the machine in each direction and at all speeds. Take note of all noises that are not normal. Locate the source of those noises. When the operation of the machine is not correct, refer to the “Troubleshooting” section of this manual. This section lists “problems” and “probable causes”.